Two-stroke combustion engine



' Aug. 1o 1926.

G. DOLNE-DEHAN TWO-STROKE COMBUSTION ENGINE Filed July l1 1924 lowered.

Patented Aug. 10, 1926.

' UNITED STATES 1,595,239 PATENT OFFICE. i

GASTON IDOLNE-IDEHAN, 0F JUAN LES PINS, FRANCE.

'Two-srnoxn coMBUs'TIoN ENGINE.

Appueation mea July 11, 1924, serial No. 725,510, and in Belgium my 1e, 1923.

This invention relates to two-stroke engines in whichthe fuel supply is effected by a plurality of spraying nozzles simultaneously projecting the fuel on a metallic and electrically heated band while the superheated air from the scavenging charge energetically stirs the jets of liquid in the proximity of the ignition device.

This arrangement` permits in high pressure engines, the air to be first compressed alone and the fuel to be thereafter injected at the moment of combustion which obviously must be as brief and complete as possible.

In the accompanying drawing wherein an approved embodiment of the invention is illustrated,

Fig. 1 is a fragmentary vertical section of an engine constructed in accordance with the invention showing the piston in elevated position.

Fig. 2 is a similar view showing the piston Fig. 3 is a diagrammatic view illustrating the disposition of the various fuel nozzles and air channels with respect to the igniting device.

The piston 1 carrying a sleeve like extension is arranged within the cylinder 2 and is adapt-ed as it approaches the limit of its down stroke to uncover the c exhaust port 3 which latter occupies substantially the entire circumference of the cylinder.

Immediately subsequent to the uncovering of the port 3, a series of inclined ports 4 uncover the upwardly converging passages 5 formed in the cylinder wall and the latter ports coat-ting' with the port 3 effectively scavenge the cylinder throughout its entire length. The upper end of the cylinder is closed by a head 7 having the usual chamber therein for the passage of a cooling medium. Between the head 7 and the cylinder 2 is an annular chamber 8' receiving the sleeve extension of the piston during the upstroke of the latter. .V

The fluid sealing of the space 8 is secured by means'of a series of packing rings 9 disposed above and below the passages 4. wider packing ring 10 surrounding thevupper part of the piston sleeve which collects a small 'quantity of oil on the cylinder wall and brings it over vthe edge of the sleeve toward the surface of the cylinder head.

The dimension of the annular chamber 8 is calculated so the compression increased more rapidly in this chamber than in the combustlon chamber, for an equal displacement of the piston.

The 'pressure in the space below the piston isrelieved by ports 11 which are uncoveredv by the lower edge of the piston during the upward stroke thereof. An annular channel 12 in communication with the atmosphere supplies these ports which latter terminate in the cylinder at the same level as the scavenging passages 5 and are arranged intermediate the latter.

The injection of the 'liquid fuel is effected by means o f the spraying nozzles 13 arranged about the cylinder and adapted to be uncovered when the piston approaches the limit of its 11p-stroke.

The spraying nozzles are inclined corre'- spondingly to the passages 4 and are arranged to direct jets of fuel tangentially towards a circular oove 14 formed on the inner side of the cylinder head. The wall of which groove is faced with- -a metallic refractory band of platinum, nickel or other duralble and non-fusible alloy rolled over nearly The groove 14, in addition to insulating and by contact with the walls, and causes thev air to pass through the channels 16 which are directed in the same tangential direction as the fuel jets towards the ignition groove 14 as clearly disclosed in Fi 3.

It is clearly evident that the simu taneous action of the nozzles spraying the liquid fuel A in the form of very fine jets and of the channels blowing out hot air, produces in the groove 14 an eddy carrying away the rvapors produced by the highly heated band mixing it with the air of the combustion chamber and preventing the combustion being localized' at the point of ignition. At the same time, the admission of air through the channels 16 tends lation of carbon on the heating surface of the band.

Among the advantages obtained by this arrangement as compared with those valready known, it will be observed that the nozzles being covered during the whole period of compression and combustion, except the moment of their operation cannot possibly permit the liquid fuel to escape into the combustion chamber, a defect Well known in present types of engines which frequently results in damage and accident. Furthermore, the nozzles are protected from deterioration caused by the high temperature of the cylinder. l

Manometric needles 19 permit the individua-l regulation and cleaning of each nozzle. When the engine is inoperative the cylinder head may be removed and the action of the nozzlesinspected. Regulation is possible during operation and the multiplicity of nozzles renders the operation of the nozzle more reliable as in case of damage or the like to one or more of the nozzles, the others may be so adjusted as to make up for the deficiency in fuel supply.

The current necessary for the ,operation of the heating band is comparatively slight and use may be made of a small reducer transformer fed by a magneto or an alternator actuated by the engineduring operation of the latter or by hand during its inoperativeness.

That I claim as new, and desire to secure by Letters Patent is 1. In a two-stroke engine, a cylinder, a piston mounted in the cylinder having a sleeve like extension, a crank case, said piston having inclined ports therein at the base of the sleeve extension, means for conducting compressed air from the engine crank case to the combustion chamber, a plurality of spraying nozzles arranged in the Wall of the cylinder, and means for regulating and cleaning each nozzle relative to the other nozzle.

to prevent the rapid accumu- 2. In a two-stroke engine, a cylinder, a piston mounted in the cylinder having a sleeve like extension, a crank case, said piston having inclined ports therein at the base ofthe sleeve extension, means for conducting compressed air from the engine crank case to the combustion chamber, a plurality of spraying nozzles arranged in the Wall of the cylinder.

3. An engine as claimed in claim 2 characterized by the provision of a cylinder head providing an annular chamber for receiving the extension sleeve, said cylinder head having an annular groove, an electrically heated metallic band in said groove, said nozzles being arranged to project liquid fuel tangentlally of the groove whereby the fuel comes in Contact with the metallic band.

4. An engine as claimed in claim 2 characterized by the provision of a cylinder head providing an annular chamber for receiving the extension sleeve, said cylinder head having an annular groove, an electrically heated metallic bandin said groove, said nozzles being arranged to project liquid fuel tangentially of the groove whereby the fuel comes in contact with the metallicband, a fuel supply pipe common to all of the nozzles,

land means for regulating and cleaning each nozzle individually.

5. An engine as claimed in claim 2 characterized by the provision of a cylinder head providing an annular chamber for receiving the extension sleeve, said cylinder head having an annular groove, an. electrically heated metallic band in said groove, said nozzles being arranged to project liquid fuel tangentially of the groove whereby the fuel comesin contact with the metallic band, said cylinder head having a second groove therein and channels connecting the groove, and a shoulder on the piston adapted to enter the second groove and force air through the channels into the first groove.

In testimony whereof I have signed my name to this specification.

DR. GASTON DOLNE-DEHAN. 

